1. Field of the Invention
This invention relates to the repair of damaged tissue, and more specifically, to the use of noninfectious collagen to heal damaged dural tissue.
2. Description of Related Art
The human brain and spinal cord are covered with meningeal membranes whose integrity is critical to the operation of the central nervous system. When the integrity of a person's meningeal membranes is intentionally or accidentally compromised, serious consequences may ensue, unless the membranes can be repaired.
The meningeal membrane comprises three overlapping layers of tissue, which are in order from outside to inside, the dura mater (or dura), the arachnoid and the pia mater. Repairing damaged meningeal membranes has largely focused on implantable and/or resorbable constructs (known as dural substitutes) which are grafted over the damaged dura mater and are designed to replace and/or regenerate the damaged tissue.
Integra LifeSciences Corp. markets a particularly effective dural substitute under the trademark DURAGEN. The product, which is described in U.S. Pat. No. 5,997,895, comprises a collagen matrix, is fully resorbed following complete tissue closure of the dural defect and easily conforms to complex surfaces. U.S. Pat. No. 5,997,895 discloses that collagen processed using an alkaline/salt treatment in accordance with U.S. Pat. No. 5,019,087 is an extremely effective dural replacement product that will lead to the regeneration of a patient's own functional dura. The preferred alkaline/salt treatment involves sodium hydroxide and sodium sulfate. The methods of U.S. Pat. No. 5,019,087 provide a controlled predictable pore size.
Despite the many benefits of the DURAGEN product, it is desired to provide a further improved dural substitute. In particular, it is desired to provide an improved dural substitute with enhanced suturability. It is further desired that said dural substitute be physiologically compatible (i.e., non-inflammatory, non-adhesion inducing, etc.), sufficiently noninfectious (i.e., decontaminated, etc.) to prevent the transmission of viruses and prions to dural substitute recipients, pliable, available in a variety of sizes, high in tensile strength, inert and optionally capable of forming a water-tight seal.
All references cited herein are incorporated herein by reference in their entireties.